This invention relates to self-contained batteries disposed within an enclosure provided with means for rechargeing the batteries.
A problem with prior art lantern batteries, and the like, is the potential damage which can be done to the environment (e.g., fire hazard) or in some cases to the battery if the output terminals of the battery are short-circuited. One solution to this problem is the provision of a short-circuit relay or fuse connected so that a short circuit causes the relay to trip or fuse to operate to open the circuit and prevent damaging the battery.
It is also important to know if the battery has been subjected to a short circuit condition, as this will provide imformation which will permit the use of a proper regime for recharging the battery to bring it safely to its full capacity in minimum of time. An indication that the battery has been severely discharged may also assist the manufacturer in other respects.
Another problem which has existed with such batteries is not precisely allied with the above problem, but pertains to a situation where the output voltage of the battery is not compatible with the voltage withstand capability of the load. As an example, lanterns using batteries often customarily employ 5-volt lamps or bulbs. If the output voltage of the battery under load exceeds five volts appreciably, then the lamp may be ruined unless the voltage is stepped down to a safe level near five volts.
It is a primary object of this invention to overcome all the above problems without the use of a circuit breaker or fuse.